IgE-mediated anaphylaxis after first intravenous infusion of cyclosporine.

BACKGROUND: Intravenous administration of cyclosporine, which contains Cremophor EL (a polyethoxylated castor oil; BASF, Berlin, Germany), has occasionally resulted in an anaphylactic reaction. An apparent hypersensitivity reaction (bronchospasm and decrease in blood pressure) had occurred during heart transplantation in a 59-year-old woman after intravenous infusion of cyclosporine. Subsequent oral administration of cyclosporine precipitated no reaction. OBJECTIVE: The purpose of this study was to attempt to ascertain the mechanism responsible for the anaphylactic reaction. METHODS: Hypersensitivity investigations, including total serum IgE and allergen-specific IgE quantifications, skin testing, and basophil activation tests by flow cytometric determination of CD63 upregulation were undertaken in the study patient and in two healthy control subjects who were free of medication. RESULTS: The results of intradermal testing with Cremophor EL were positive after 15 minutes in the study patient only. Both cyclosporine and Cremophor EL induced considerable activation of the basophils from our study patient, with an upregulation of CD63 expression from 1% to 39% and 55%, respectively. In contrast, the expression of CD63 on basophils from the two control subjects remained essentially unchanged. CONCLUSIONS: The negative investigative findings in the control subjects, the patient's clinical manifestations in temporal relationship to the infusion, her positive results on intradermal testing with Cremophor, the basophil activation test results, and her uneventful course after oral administration of cyclosporine strongly support the presence of IgE antibodies to Cremophor EL in our patient.